Hea-Jo Yoon

Comparison of general and epidural anesthesia in elective cesarean section for placenta previa totalis: maternal hemodynamics, blood loss and neonatal outcome.

There are few consistent guidelines in choosing anesthesia for cesarean section for a parturient with placenta previa. This prospective randomized trial was organized to compare the maternal hemodynamics, blood loss and neonatal outcome of general versus epidural anesthesia for cesarean section with the diagnosis of grade 4 placenta previa. After giving informed consent, 12 patients received general anesthesia and 13 received epidural. Intraoperative blood pressures demonstrated a more stable course in the epidural group than in the general group. Blood loss did not differ significantly between the groups (1622 +/- 775 mL vs. 1418 +/- 996 mL). General anesthesia resulted in lower immediate postoperative hematocrit level (28.1 +/- 3.5% vs. 32.5 +/- 5.0%, P < 0.05). The patients in the general group received a significantly larger transfusion than the epidural group (1.08 +/- 1.6 vs. 0.38 +/- 0.9 units, P < 0.05). The Apgar scores at 1 and 5 min were similar in the two groups (8 [4-9] vs. 8 [7-9] and 10 [6-10] vs. 9 [9-10], respectively). We concluded that epidural anesthesia is superior to general anesthesia in elective cesarean section for grade 4 placenta previa with regard to maternal hemodynamics and blood loss. There was no difference in neonatal outcome.

Nicotine decreases the activity of glutamate transporter type 3.

Nicotine, the main ingredient of tobacco, elicits seizures in animal models and cigarette smoking is regarded as a behavioral risk factor associated with epilepsy or seizures. In the hippocampus, the origin of nicotine-induced seizures, most glutamate uptake could be performed primarily by excitatory amino acid transporter type 3 (EAAT3). An association between temporal lobe epilepsy and EAAT3 downregulation has been reported. Therefore, we hypothesized that nicotine may elicit seizures through the attenuation of EAAT3 activity. We investigated chronic nicotine exposure (72 h) cause reduction of the activity of EAAT3 in a Xenopus oocyte expression system using a two-electrode voltage clamp. The roles of protein kinase C (PKC) and phosphatidylinositol 3-kinase (PI3K) were also determined. Nicotine (0.001-1 μM) resulted in a time- and dose-dependent decrease in EAAT3 activity with maximal inhibition at nicotine concentrations of 0.03 μM or higher and at an exposure time of 72 h. Vmax on the glutamate response was significantly reduced in the nicotine group (0.03 μM for 72 h), but the Km value of EAAT3 for glutamate was not altered. When nicotine-exposed oocytes (0.03 μM for 72 h) were pretreated with phorbol-12-myristate-13-acetate (PMA, a PKC activator), the nicotine-induced reduction in EAAT3 activity was abolished. PKC inhibitors (staurosporine, chelerythrine, and calphostin C) significantly reduced basal EAAT3 activity, but there were no significant differences among the PKC inhibitors, nicotine, and PKC inhibitors+nicotine groups. Similar response patterns were observed among PI3K inhibitors (wortmannin and LY294002), nicotine, and PI3K inhibitors+nicotine. In conclusion, this study suggests that nicotine decreases EAAT3 activity, and that this inhibition seems to be dependent on PKC and PI3K. Our results may provide an additional mechanism for nicotine-induced seizure.

Anesthetic review of emergency peripartum hysterectomy following vaginal and cesarean delivery: a retrospective study

Background The purpose of this study was to review incidence, indications, complications, and the anesthetic management of emergency obstetric hysterectomies. Methods This was a retrospective study of the cases of emergency obstetric hysterectomies performed at the Womans Hospital over a 3 year period between January 2008 and December 2010. The indication for surgery, anesthetic management, operating time, estimated blood loss, pre- and postoperative hemoglobin and hematocrit values, need for blood transfusion, and perioperative complications were obtained. Results During the study period there were 46 emergency obstetric hysterectomies for 20147 deliveries, giving an incidence of 2.28/1000 deliveries. The number of emergency hysterectomies was significantly higher with the cesarean deliveries than with the vaginal deliveries. The most common indication for emergency obstetric hysterectomy was placenta accreta. Postoperatively, Dissemimated Intravascular Coagulation (DIC) was the most common complication. Conclusions Abnormal placenta has been an main indication of emergency hysterectomy. Anesthesiologists should be eligible to aware of high risk of emergency hysterectomy and deal with massive hemorrhage.

Comparison of hemodynamic changes between phenylephrine and combined phenylephrine and glycopyrrolate groups after spinal anesthesia for cesarean delivery

Background Hypotension remains a common clinical problem of spinal anesthesia for cesarean delivery and phenylephrine is used as a vasopressor to address this. However, phenylephrine reduces maternal cardiac output (CO) due to reflex bradycardia. Glycopyrrolate is safe for the fetus, and increases heart rate (HR). Using a noninvasive measure of CO, we compared maternal hemodynamic changes between the phenylephrine only group (group P) and the phenylephrine plus glycopyrrolate group (group PG). Methods In this randomized study, 60 women scheduled for elective cesarean delivery were allocated to group P (n = 30) or group PG (n = 30). In both groups, phenylephrine was infused at 50 µg/min. This infusions stopped if systolic blood pressure (SBP) was higher than the baseline value, and phenylephrine 100 µg was injected if SBP was lower than 80% of the baseline value from spinal anesthesia to delivery. In group PG, glycopyrrolate 0.2 mg was injected intravenously after spinal anesthesia. Hemodynamic parameters, such as SBP, heart rate (HR), stroke volume index (SVI), cardiac index (CI) were measured before and until 15 min after spinal anesthesia. Results There were no significant differences in SBP and SVI compared to the baseline value in each group and between the two groups. HR and CI reduced significantly from 8 min to 15 min in group P compared to the baseline value as well as group PG for each time-point. However, HR and CI were maintained in group PG. Conclusions The use of glycopyrrolate added to phenylephrine infusion to prevent hypotension by spinal anesthesia for cesarean delivery was effective in maintaining HR and CI.

Comparing epidural surgical anesthesia and spinal anesthesia following epidural labor analgesia for intrapartum cesarean section: a prospective randomized controlled trial

Background The conversion of epidural labor analgesia (ELA) to epidural surgical anesthesia (ESA) for intrapartum cesarean section (CS) often fails, resulting in intraoperative pain. Spinal anesthesia (SA) can provide a denser sensory block than ESA. The purpose of this prospective, non-blinded, parallel-arm, randomized trial was to compare the rate of pain-free surgery between ESA and SA following ELA for intrapartum CS. Methods Both groups received continuous epidural infusions for labor pain at a rate of 10 ml/h. In the ESA group (n = 163), ESA was performed with 17 ml of 2% lidocaine mixed with 100 µg fentanyl, 1 : 200,000 epinephrine, and 2 mEq bicarbonate. In the SA group (n = 160), SA was induced with 10 mg of 0.5% hyperbaric bupivacaine and 15 µg fentanyl. We investigated the failure rate of achieving pain-free surgery and the incidence of complications between the two groups. Results The failure rate of achieving pain-free surgery was higher in the ESA group than the SA group (15.3% vs. 2.5%, P < 0.001). There was no statistical difference between the two groups in the rate of conversion to general anesthesia; however, the rate of analgesic requirement was higher in the ESA group than in the SA group (12.9% vs. 1.3%, P < 0.001). The incidence of high block, nausea, vomiting, hypotension, and shivering and Apgar scores were comparable between the two groups. Conclusions SA after ELA can lower the failure rate of pain-free surgery during intrapartum CS compared to ESA after ELA.

The effects on Apgar scores and neonatal outcomes of switching from a combination of phenylephrine and ephedrine to phenylephrine alone as a prophylactic vasopressor during spinal anesthesia for cesarean section

Background Ephedrine, unlike phenylephrine, has a dose-related propensity to depress fetal pH during spinal anesthesia during cesarean section. A low arterial umbilical cord pH has a strong association with neonatal mortality and morbidity. The purpose of this retrospective study was to investigate influences of vasopressor change on Apgar scores and adverse neonatal outcomes in cesarean section. Methods In obstetric anesthesia, we changed the prophylactic vasopressor from a combination of phenylephrine and ephedrine to phenylephrine alone in 2000. We evaluated the impact of vasopressor change on Apgar scores (1 and 5 min), incidence of Apgar score < 7 (1 and 5 min), neonatal seizure, continuous positive airway pressure (CPAP), intermittent positive pressure ventilation (IPPV), intraventricular hemorrhage (IVH), periventricular leucomalacia (PVL), and hypoxic ischemic encephalopathy (HIE) in low-risk elective cesarean sections during a period when the combination of phenylephrine and ephedrine was used (2008-2009, two years) and the period of phenylephrine use alone (2011-2012, two years). Results There were no differences in Apgar scores (1 and 5 min), the incidence of 5 min Apgar score < 7, neonatal seizure, CPAP, IPPV, IVH, PVL, and HIE between the two time periods. However, the incidence of 1 min Apgar < 7 was decreased during the period of phenylephrine use compared with the period of phenylephrine and ephedrine use (P = 0.002). Conclusions Conversion from a combination of phenylephrine and ephedrine to phenylephrine alone as a prophylactic anti-hypotensive drug during spinal anesthesia for cesarean section in low-risk pregnancy may be associated with a significant decrease in the incidence of 1 min Apgar < 7.

Prophylactic antiemetic effects in gynecologic patients receiving fentanyl IV-patient controlled analgesia: comparison of combined treatment with ondansetron and dexamethasone with metoclopramide and dexamethasone.

Background This study was conducted to compare the efficacy of a combination of ondansetron and dexamethasone with that of metoclopramide and dexamethasone for prevention of postoperative nausea and vomiting (PONV) in gynecologic patients receiving fentanyl IV-patient controlled analgesia. Methods One hundred patients were divided into two groups at random. In Group O, 5 mg of dexamethsone was administered after tracheal intubation, while 4 mg of ondansetron was administered at the end of surgery. In Group M, 5 mg of dexamethsone was administered after tracheal intubation and 20 mg metoclopromide was administered at the end of surgery. During the experiment, the PONV was evaluated at regular intervals. In addition, the incidence of nausea, and vomiting and the numerical rating scale (NRS) of nausea was measured (range, 0-10). Results The overall incidence of PONV in Group O was 22/50 (44%) while that in Group M was 19/50 (38%). There were no significant differences in the incidence of nausea, moderate to severe nausea (NRS of nausea, 4-10), or vomiting between groups. Conclusions Treatment with a combination of 20 mg metoclopramide and 5 mg dexamethasone is an effective, safe, and inexpensive way to prevent PONV when compared to treatment with 4 mg ondansetron and 5 mg dexamethasone.

Dexmedetomidine increases the activity of excitatory amino acid transporter type 3 expressed in Xenopus oocytes: The involvement of protein kinase C and phosphatidylinositol 3-kinase

Dexmedetomidine, an α2 adrenergic agonist, has neuroprotective and anticonvulsant properties in addition to its sedative and anxiolytic effects. We hypothesized that dexmedetomidine would increase the activity of excitatory amino acid transporter type 3 (EAAT3) and that this effect would involve protein kinase C (PKC) and phosphatidylinositol 3-kinase (PI3K), two protein kinases known to regulate EAAT3 activity. EAAT3 was expressed in Xenopus oocytes by injecting its mRNA. Two-electrode voltage clamping was used to record membrane currents before, during, and after application of 30 μM l-glutamate in the presence of 0.1-30 nM dexmedetomidine. Dexmedetomidine-treated oocytes were also exposed to a PKC activator (phorbol-12-myristate-13-acetate [PMA]), PKC inhibitors (chelerythrine, staurosporine, and calphostin C), and PI3K inhibitors (wortmannin and LY294002) before current measurement. Dexmedetomidine application resulted in a concentration-dependent increase in the EAAT3 activity in response to l-glutamate. The kinetic study showed that dexmedetomidine significantly increased the Vmax without changing Km. Treatment of oocytes with PMA significantly increased transporter currents compared with controls, but treatment with dexmedetomidine plus PMA did not further increase the response compared with PMA or dexmedetomidine alone. In addition, pre-treatment of oocytes with PKC inhibitors and PI3K inhibitors significantly abolished the dexmedetomidine-enhanced EAAT3 activity. These results suggest that dexmedetomidine increases the activity of EAAT3 expressed in Xenopus oocytes. PKC and PI3K seem to mediate this effect. These findings may explain the neuroprotective and anticonvulsant effects of dexmedetomidine.

Intravascular migration of a previously functioning epidural catheter

The use of regional anesthesia for spontaneous delivery and cesarean section has significantly increased, due to both patient demand and the reduced risk of maternal mortality and morbidity compared with general anesthesia [1]. Despite the benefits, inadvertent intravascular and intrathecal injection of a local anesthetic may cause severe complications, including systemic toxicity, total spinal anesthesia, and a high spinal block.

Spinal anesthesia during cesarean section in a patient with severe osteogenesis imperfecta - A case report -

Obstetric anesthesia in a parturient with severe osteogenesis imperfecta is challenging in many aspects, particularly concerning maternal pathophysiological problems and the technical difficulties of anesthesia. Here, we report a case of successful spinal anesthesia, instead of general or epidural anesthesia, during a cesarean delivery in a patient with severe osteogenesis imperfecta.